CRC-aided iterative optimal detection for MIMO-OFDM systems with linear precoding

This paper proposes a novel receiver structure based on soft information for linearly precoded MIMO-OFDM systems. The architecture combines an MMSE-based front end with an iterative technique based on maximum likelihood detection (MLD) in a structure that exhibits two very attractive features. Firstly, it can fully exploit the diversity benefits of spreading the information symbols in the space and frequency domains by optimally estimating them. Secondly, and under the realistic assumption of the presence of a cyclic redundancy check (CRC) mechanism, the far more computationally demanding MLD component needs only be used when the MMSE front end has failed. Simulation results reveal that the MLD iterative mechanism adds only a negligible amount of computations to the simple MMSE detector while significantly improving its performance.